1. Field of the Invention
The present invention relates to skis and to snowmobiles, and more particularly to a quad parabolic snowmobile ski for steering a snowmobile.
2. Description of the Related Art
Skis have been used for transportation for centuries, including skis for attachment directly to the feet and skis for attachment to sleds, sleighs, and various other snow vehicles, including snowmobiles. Only within the last fifty years or so have these skis incorporated or included what have been referred to as wear or steering keel bars, runners, skags, and the like. A typical runner blade may be attached by studs to the bottom surface of a ski, with the front and rear ends of the bar bent to tuck into the bottom of the ski. This method of attachment is still popular today.
A wear, steering keel, or runner bar can perform several functions. As one name implies, a wear bar is used to lengthen the life of the under or bottom surface of the ski by focusing the contact or wear on the bar when in contact with the ground or hard surfaces. As a steering keel bar, the bar extends downwards, as in a watercraft, to stabilize and improve the steering responsiveness and capability of the ski. Skis with steering keel bars are now in commonplace usage as steering skis for snowmobiles. However, many present designs incorporating a steering keel still do not provide tight, precision, high performance level steering.
International Patent No. WO 83/03554, published Oct. 27, 1983, appears to disclose a wearable mono-ski with improved steering due to rear and front openings in the ski body. The '554 patent does not appear to address a ski appropriate for a snowmobile.
Thus, until now the lack of precision in turning capability has remained and often resulted in sloppy high speed turning characteristics that are evidenced by a plowing effect in a current direction of travel, rather than a controlled, turning effect in a steered direction. At high speeds, this effect can be dangerous and result in collision with objects in the path of the snowmobile even though the operator tries to steer around the objects.
Keel designers are continuously attempting to deal with this problem by modifying keel lengths and geometries to improve steering characteristics, yet maintain ease of steering from driver inputs. Nevertheless, the problem of precision, predictable and relatively effortless steering remains to be solved.
Thus, a snowmobile ski solving the aforementioned problems is desired.